1. Field of the Invention
The present invention relates generally to computer implemented systems for displaying information stored in a file in a computer to a user, and in particular, to a method and apparatus for proportional auto-scrolling through data displayed in a window wherein the scrolling speed and direction is determined by the cursor position on the display.
2. Description of the Related Art
Presenting information to a user with a computer using multiple windows on a display device with a graphical user interface is well known in the art. Also well known in the art is the technique of using a pointing device, such as a mouse or a trackball to select data within the file before a function is applied to the data. Further, the method of using the pointing device to provide graphical input to the window is also well known.
However, these techniques present some unique problems. Typically, the information contained in the file is greater than what can be displayed in the window at one time. Similarly, the user may want to provide graphical input which exceeds the window size. Hence, some method must be employed to allow the user to use the pointing device to select or input information which exceeds the window boundaries.
One possible method to solve this problem is to merely enlarge the window. However, this is useful only when the amount of data is less than the window size.
Another method to solve this problem is to use auto-scroll functions, which are well known in the art. Using auto-scroll methods, the data displayed in the window is automatically scrolled without using the scroll bars when the pointing device is "dragged" outside the window.
These prior art auto-scroll methods, however, are inherently limited and do not fully utilize the capabilities of the graphical user interface. For example, the prior art auto-scrolling methods do not allow the user to control the speed of the auto-scroll. The net result is that the speed of the auto-scroll is often too fast or too slow. The speed of the auto-scroll may be too slow in situations where the user desires to scroll only a small part of the file that is not displayed in the window. Conversely, the speed of the auto-scroll may be too fast in situations where the user desires to select a large amount of text. Analogous problems exist when the user desires to input graphical user inputs larger than the window size. This situation may occur when using paint, draw, or CAD (computer automated design) programs.
Therefore, there exists a need for an intuitive proportional auto-scroll capability for information presented in a window.